I've been using a C-More Railway Sight on my 617 for a number of years with a 12 MOA Dot. It's large but works well for Steel Challenge Matches where targets range from 10 inches at 7 yards, 12 inches out to 25 yards and 18 X 24 inches out to 35 yards.

I found a Burris Fast Fire II AR and wanted a change just to see how well it works. It only has a 3 MOA dot and I was curious if my groups would get tighter. They did.

I started sighting in at 7 yards and wanted to be 1 inch low of center. This typically gives me dead center at 15 yards ( where most of the targets are ) and only a few inches high at 35 yards. Easily enough to hit thosle big guys.

I used an EGW mount and it was easy to set up the sight. It only takes 2 screws so I had to find a plug got the front screw hole. Without the plug hot gasses, smoke and lead will cover the dot. Fortunately I have a bunch of these screw so there should be no trouble.

Everything is now sighter in and ready to go. Only other situation I need to be comfortable with is if the dot will wash out in bright sunlight.